:root{
  --navy:#1b2a5b;
  --navy-dark:#131f45;
  --blue:#2b4bb5;
  --blue-light:#eaf1fb;
  --green:#3d9c6a;
  --green-light:#eaf6ef;
  --purple:#7a5cb8;
  --purple-light:#f2edfa;
  --orange:#b07a2a;
  --orange-light:#fdf3e3;
  --red:#c74a4a;
  --red-light:#fdeaea;
  --text:#22293b;
  --muted:#5b6478;
  --line:#e3e8f2;
  --radius:18px;
  --shadow:0 8px 30px rgba(27,42,91,.10);
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  font-family:"Segoe UI",-apple-system,BlinkMacSystemFont,Roboto,Arial,sans-serif;
  color:var(--text);
  background:#f5f7fc;
  line-height:1.55;
}
a{text-decoration:none;color:inherit}
ul{list-style:none}
button{font-family:inherit;cursor:pointer}
input,textarea,select{font-family:inherit;font-size:.95rem}
.container{max-width:1200px;margin:0 auto;padding:0 20px}

/* ================= HEADER ================= */
header{
  background:var(--navy);
  color:#fff;
  position:sticky;top:0;z-index:100;
  box-shadow:0 2px 12px rgba(0,0,0,.25);
}
.nav{display:flex;align-items:center;justify-content:space-between;height:66px;gap:12px}
.logo{display:flex;align-items:center;gap:12px;font-weight:800;letter-spacing:.5px;line-height:1.15;font-size:.95rem}
.logo .mark{
  width:40px;height:40px;border-radius:10px;
  background:linear-gradient(135deg,#3b5bd6,#7a5cb8);
  display:grid;place-items:center;font-size:1.2rem;
}
.nav ul{display:flex;gap:4px;flex-wrap:wrap;align-items:center}
.nav ul a{padding:8px 12px;border-radius:8px;font-size:.9rem;opacity:.9;transition:.2s;display:block}
.nav ul a:hover{background:rgba(255,255,255,.12);opacity:1}
.nav ul a.active{background:rgba(255,255,255,.18);opacity:1;font-weight:700}
.burger{display:none;background:none;border:none;color:#fff;font-size:1.6rem}
.search-btn{
  background:rgba(255,255,255,.12);border:none;color:#fff;
  width:38px;height:38px;border-radius:10px;font-size:1rem;transition:.2s;
}
.search-btn:hover{background:rgba(255,255,255,.25)}

/* ================= PAGE HERO ================= */
.page-hero{
  color:#fff;padding:52px 0 46px;position:relative;overflow:hidden;
  background:linear-gradient(135deg,var(--navy),#2c3e86);
}
.page-hero.teacher{background:linear-gradient(135deg,#2b4bb5,#1b2a5b)}
.page-hero.student{background:linear-gradient(135deg,#43a873,#22603f)}
.page-hero.digital{background:linear-gradient(135deg,#8a6cc9,#4c357f)}
.page-hero.assessment{background:linear-gradient(135deg,#d1913c,#8a5a1c)}
.page-hero h1{font-size:clamp(1.7rem,4vw,2.5rem)}
.page-hero p{margin-top:10px;max-width:720px;opacity:.92}
.breadcrumbs{font-size:.85rem;opacity:.75;margin-bottom:14px}
.breadcrumbs a:hover{text-decoration:underline}

/* ================= SECTIONS / PANELS ================= */
section.block{padding:44px 0 0}
section.block:last-of-type{padding-bottom:64px}
.panel{background:#fff;border-radius:var(--radius);box-shadow:var(--shadow);padding:32px}
.panel h2{color:var(--navy);font-size:1.45rem;display:flex;align-items:center;gap:10px;margin-bottom:8px}
.panel .sub{color:var(--muted);margin-bottom:22px}
.section-title{text-align:center;color:var(--navy);font-size:clamp(1.5rem,3vw,2rem);margin-bottom:36px}

/* ================= CARDS ================= */
.grid-2{display:grid;grid-template-columns:repeat(2,1fr);gap:20px}
.grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.grid-4{display:grid;grid-template-columns:repeat(4,1fr);gap:18px}
.card{
  background:#fff;border-radius:14px;padding:22px;box-shadow:var(--shadow);
  border:1px solid var(--line);transition:transform .2s;
}
.card:hover{transform:translateY(-3px)}
.card .ic{font-size:1.7rem}
.card h4{margin:10px 0 6px;color:var(--navy)}
.card p{font-size:.9rem;color:var(--muted)}
.card .meta{margin-top:12px;display:flex;gap:8px;flex-wrap:wrap}
.chip{background:var(--blue-light);color:var(--navy);border-radius:999px;padding:4px 12px;font-size:.78rem;font-weight:600}
.chip.green{background:var(--green-light);color:#276445}
.chip.purple{background:var(--purple-light);color:#5f43a0}
.chip.orange{background:var(--orange-light);color:var(--orange)}

/* ================= BUTTONS ================= */
.btn{
  display:inline-block;background:var(--blue);color:#fff;border:none;
  padding:11px 24px;border-radius:10px;font-weight:700;font-size:.93rem;transition:.2s;
}
.btn:hover{background:#2340a3;transform:translateY(-1px)}
.btn.green{background:var(--green)}
.btn.green:hover{background:#2e7d54}
.btn.purple{background:var(--purple)}
.btn.purple:hover{background:#5f43a0}
.btn.ghost{background:transparent;color:var(--blue);border:2px solid var(--blue)}
.btn.ghost:hover{background:var(--blue-light);transform:none}
.btn.small{padding:7px 16px;font-size:.85rem}
.btn.danger{background:var(--red)}
.btn:disabled{opacity:.5;cursor:not-allowed;transform:none}

/* ================= TABS ================= */
.tabs{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:22px}
.tab-btn{
  background:#fff;border:1px solid var(--line);border-radius:10px;
  padding:10px 20px;font-weight:600;font-size:.9rem;color:var(--muted);transition:.2s;
}
.tab-btn.active{background:var(--navy);color:#fff;border-color:var(--navy)}
.tab-pane{display:none}
.tab-pane.active{display:block;animation:fadeIn .3s}
@keyframes fadeIn{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:none}}

/* ================= ACCORDION ================= */
.accordion{border:1px solid var(--line);border-radius:12px;overflow:hidden;background:#fff}
.acc-item + .acc-item{border-top:1px solid var(--line)}
.acc-head{
  width:100%;display:flex;justify-content:space-between;align-items:center;gap:12px;
  background:none;border:none;padding:16px 20px;font-size:.98rem;font-weight:700;
  color:var(--navy);text-align:left;
}
.acc-head::after{content:"▾";transition:.25s;color:var(--muted)}
.acc-item.open .acc-head::after{transform:rotate(180deg)}
.acc-body{display:none;padding:0 20px 18px;color:var(--text);font-size:.93rem}
.acc-item.open .acc-body{display:block;animation:fadeIn .25s}
.acc-body ol,.acc-body ul{padding-left:20px;margin:8px 0}
.acc-body ul{list-style:disc}
.acc-body ol{list-style:decimal}

/* ================= TABLES ================= */
.table-wrap{overflow-x:auto}
table.data{width:100%;border-collapse:collapse;font-size:.9rem;background:#fff}
table.data th{
  background:var(--navy);color:#fff;padding:11px 14px;text-align:left;font-weight:600;white-space:nowrap;
}
table.data td{padding:10px 14px;border-bottom:1px solid var(--line);vertical-align:top}
table.data tr:nth-child(even) td{background:#f8fafd}

/* ================= STEPS ================= */
.steps{display:flex;flex-direction:column;gap:14px}
.step{display:flex;gap:16px;align-items:flex-start}
.step .num{
  flex:0 0 40px;height:40px;border-radius:50%;background:var(--blue);color:#fff;
  display:grid;place-items:center;font-weight:800;
}
.step.green .num{background:var(--green)}
.step h5{color:var(--navy);font-size:1rem;margin-bottom:3px}
.step p{font-size:.9rem;color:var(--muted)}

/* ================= QUIZ ================= */
.quiz-q{border:1px solid var(--line);border-radius:14px;padding:22px;background:#fff;margin-bottom:18px}
.quiz-q h4{color:var(--navy);margin-bottom:6px}
.quiz-q .context{
  background:var(--blue-light);border-radius:10px;padding:12px 16px;
  font-size:.9rem;margin:10px 0 14px;
}
.quiz-q .opts{display:flex;flex-direction:column;gap:8px}
.quiz-q .opt{
  display:flex;align-items:center;gap:10px;border:1.5px solid var(--line);
  border-radius:10px;padding:10px 14px;font-size:.92rem;cursor:pointer;transition:.15s;background:#fff;
}
.quiz-q .opt:hover{border-color:var(--blue)}
.quiz-q .opt.selected{border-color:var(--blue);background:var(--blue-light)}
.quiz-q .opt.correct{border-color:var(--green);background:var(--green-light)}
.quiz-q .opt.wrong{border-color:var(--red);background:var(--red-light)}
.quiz-q .expl{
  display:none;margin-top:12px;border-left:4px solid var(--green);
  background:var(--green-light);border-radius:0 10px 10px 0;padding:10px 14px;font-size:.88rem;
}
.quiz-q.answered .expl{display:block}
.quiz-result{
  border-radius:14px;padding:26px;text-align:center;display:none;
  background:linear-gradient(135deg,var(--blue-light),#fff);border:1px solid var(--line);
}
.quiz-result .score{font-size:2.4rem;font-weight:800;color:var(--navy)}
.progress-bar{height:10px;border-radius:999px;background:var(--line);overflow:hidden;margin:12px 0}
.progress-bar span{display:block;height:100%;background:linear-gradient(90deg,var(--green),#6fc492);border-radius:999px;transition:width .5s}

/* ================= FORMS ================= */
.form{display:flex;flex-direction:column;gap:14px}
.form label{font-weight:600;font-size:.9rem;color:var(--navy)}
.form input,.form textarea,.form select{
  width:100%;border:1.5px solid var(--line);border-radius:10px;padding:11px 14px;
  background:#fff;transition:.2s;
}
.form input:focus,.form textarea:focus,.form select:focus{outline:none;border-color:var(--blue)}
.form textarea{min-height:100px;resize:vertical}
.field{display:flex;flex-direction:column;gap:6px}
.form-row{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.notice{
  border-radius:10px;padding:12px 16px;font-size:.9rem;display:none;
}
.notice.ok{display:block;background:var(--green-light);color:#276445;border:1px solid #bfe3cf}

/* ================= CHAT (AI Navigator) ================= */
.chat{border:1px solid var(--line);border-radius:16px;background:#fff;display:flex;flex-direction:column;height:460px;overflow:hidden}
.chat-head{background:linear-gradient(135deg,#43a873,#2e7d54);color:#fff;padding:14px 18px;font-weight:700;display:flex;gap:10px;align-items:center}
.chat-body{flex:1;overflow-y:auto;padding:18px;display:flex;flex-direction:column;gap:10px;background:#f8fafd}
.msg{max-width:78%;padding:10px 14px;border-radius:14px;font-size:.9rem;white-space:pre-line}
.msg.bot{background:#fff;border:1px solid var(--line);border-bottom-left-radius:4px;align-self:flex-start}
.msg.user{background:var(--blue);color:#fff;border-bottom-right-radius:4px;align-self:flex-end}
.chat-input{display:flex;gap:10px;padding:12px;border-top:1px solid var(--line);background:#fff}
.chat-input input{flex:1;border:1.5px solid var(--line);border-radius:10px;padding:10px 14px}
.chat-input input:focus{outline:none;border-color:var(--green)}
.suggests{display:flex;gap:8px;flex-wrap:wrap;padding:0 12px 12px;background:#fff}
.suggests button{
  background:var(--green-light);border:1px solid #bfe3cf;color:#276445;
  border-radius:999px;padding:5px 13px;font-size:.78rem;font-weight:600;
}

/* ================= NOTEBOOK ================= */
.note-item{border:1px solid var(--line);border-radius:12px;padding:16px 18px;background:#fff;margin-bottom:12px}
.note-item h5{color:var(--navy);display:flex;justify-content:space-between;gap:10px;flex-wrap:wrap}
.note-item .date{font-size:.78rem;color:var(--muted);font-weight:400}
.note-item p{font-size:.9rem;margin-top:6px;white-space:pre-line}
.note-item .actions{margin-top:10px;display:flex;gap:8px}

/* ================= RANGE / SELF ASSESSMENT ================= */
.range-row{display:grid;grid-template-columns:1fr 200px 44px;gap:14px;align-items:center;padding:10px 0;border-bottom:1px solid var(--line);font-size:.92rem}
.range-row:last-of-type{border-bottom:none}
.range-row input[type=range]{width:100%;accent-color:var(--blue)}
.range-val{font-weight:800;color:var(--navy);text-align:center}

/* ================= SEARCH MODAL ================= */
.modal{
  display:none;position:fixed;inset:0;background:rgba(15,23,52,.55);
  z-index:200;padding:80px 20px 20px;justify-content:center;align-items:flex-start;
}
.modal.open{display:flex}
.modal-box{background:#fff;border-radius:16px;width:100%;max-width:620px;overflow:hidden;box-shadow:0 20px 60px rgba(0,0,0,.35)}
.modal-box input{width:100%;border:none;padding:18px 22px;font-size:1.05rem;border-bottom:1px solid var(--line)}
.modal-box input:focus{outline:none}
.search-results{max-height:380px;overflow-y:auto}
.search-results a{display:block;padding:13px 22px;border-bottom:1px solid var(--line);transition:.15s}
.search-results a:hover{background:var(--blue-light)}
.search-results a b{color:var(--navy);display:block;font-size:.95rem}
.search-results a span{font-size:.8rem;color:var(--muted)}
.search-empty{padding:22px;text-align:center;color:var(--muted);font-size:.9rem}

/* ================= FOOTER ================= */
footer{background:var(--navy-dark);color:#aab3d0;padding:26px 0;font-size:.88rem;margin-top:64px}
footer .container{display:flex;justify-content:space-between;flex-wrap:wrap;gap:10px}

/* ================= MISC ================= */
.badge{background:#fff;border:1px solid var(--line);border-radius:999px;padding:8px 18px;font-size:.88rem;font-weight:600;color:var(--navy);box-shadow:var(--shadow)}
.toolbar{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:20px}
.hidden{display:none!important}
.mt{margin-top:18px}
.center{text-align:center}

/* ================= RESPONSIVE ================= */
@media (max-width:960px){
  .grid-2,.grid-3{grid-template-columns:1fr}
  .grid-4{grid-template-columns:repeat(2,1fr)}
  .form-row{grid-template-columns:1fr}
  .range-row{grid-template-columns:1fr 120px 40px}
  .nav ul{
    display:none;position:absolute;top:66px;left:0;right:0;
    background:var(--navy);flex-direction:column;padding:12px 20px 18px;gap:2px;align-items:stretch;
  }
  .nav ul.open{display:flex}
  .burger{display:block}
}
@media (max-width:560px){
  .grid-4{grid-template-columns:1fr}
  .panel{padding:22px}
}
@media print{
  header,footer,.toolbar,.btn,.burger,.search-btn{display:none!important}
  body{background:#fff}
  .panel{box-shadow:none;border:1px solid #ccc}
}